function login() {
    var login = document.getElementById('login');
    var nav_li = document.getElementById('nav').getElementsByTagName('li');
    login.style.display = 'none';
    for (var i = 0; i < nav_li.length; i++) {
        nav_li[i].style.width = '25%';
    }
}

function unlogin() {
    var personal = document.getElementById('personal');
    var nav_li = document.getElementById('nav').getElementsByTagName('li');
    personal.style.display = 'none';
    for (var i = 0; i < nav_li.length; i++) {
        nav_li[i].style.width = '25%';
    }
}